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Core i9-13900K Thermal Results

No Power Limits Cinebench Results

With Raptor Lake’s i9-13900K pushing speeds of 5.5ghz+, even the strongest of coolers hit TJ Max while running Cinebench R23 and other demanding scenarios. As the 13900K is designed to aim for its top safe temperature, we’ll be comparing the overall benchmark score and the CPU’s clock speeds instead.

The results below are for a 10-minute testing run. But to be sure that was sufficiently long to tax the cooler, we also retested both Thermalright’s Assassin X 120 R SE and DeepCool’s LT720 with a 30-minute Cinebench test. The results didn’t change much at all with the longer test: The average clock speeds maintained dropped by 29mhz on DeepCool’s LT720 and 31mhz on Thermalright’s Assassin X 120 R SE. Looking at this another way, that’s an incredibly small 0.6% difference in clock speeds maintained, a margin of error difference that tells us that the 10 minute tests are indeed long enough to properly test the coolers.

DeepCool AG400 — (Image credit: Tom's Hardware)

Because of the difficulty of cooling the i9-13900K in this workload, we feel the best way to compare coolers here is to record the average power consumption of the CPU. DeepCool’s AG400 does alright here, cooling about 247W on average, placing it in the middle of the pack as far as performance goes (in comparison to the other coolers tested with the new CPU so far).

We’re also showing the total Cinebench R23 benchmark scores to show how little is lost – or gained – with different cooling solutions. Between the weakest and strongest coolers, we have total benchmark score variance of roughly 13%. DeepCool’s AG400 sits right in the middle of the scores again, providing 94% of the benchmark score of the strongest AIO we’ve tested thus far.

As Cinebench R23’s multi-core benchmark will push coolers to their limits, it’s also a great test for recording the worst-case scenario of fan noise levels. Here, DeepCool’s AG400 ran a bit louder than most other coolers we’ve tested with Raptor Lake, but quieter than the IceSLEET G6 Stealth and DeepCool’s LT720 AIO.

200W Cinebench Results

When restricting power consumption to a more reasonable 200W, the AG400 is basically tied with Thermalright’s Assassin 120 R SE and the IceSLEET G6 Stealth.

Looking at acoustic levels here, the AG 400’s performance is still on the noisier side of things. It’s certainly quieter than Iceberg Thermal’s IceSLEET G6 Stealth, but significantly louder than Thermalright’s Assassin 120 R SE.

125W Cinebench Results

The lowest power limit I test at is 125W, mainly because this is also the lowest level where I can reliably measure noise measurements. Lower power consumption causes the noise of the CPU cooler to fall below the noise created by the system fans (even while restricted to 35% speed).

When limited to 125W, DeepCool’s AG400 runs silently and is essentially indistinguishable from the rest of the system fans. It does run a bit warmer than most other coolers tested here, but this isn’t a cause for concern given that the increased temperature here doesn’t impact performance.

Conclusion

At only $30, DeepCool’s AG400 offers good value and decent performance – even when paired with CPUs like Intel’s i9-13900K. While it does get a bit louder than other coolers in the heaviest workloads, in less thermally taxing scenarios (which should be the vast majority of the time) the AG400 runs whisper quiet and makes a great pairing with any modern CPU.